Ammunition



Nov. 19, 1935. A. CAMPB ELL 2,021,498

I AMMUNITION Filed March 16, 1934 Fig 1 IN VEN TOR.

ALLAN CAMPBELL MW fiTORNEY Patented Nov. 19, 1935 UN ETED STAT PATENTOFFICE AMMUNITION of Delaware Application March 16, 1934, Serial No.715,831

7 Claims.

This invention relates to anvils for ammunition primers, andcontemplates certain improvements in the form of anvils with a view toimproving their functioning and simplifying their manufacture.

In Patent No. 1,900,159, March '7, 1933, the present inventor hasdisclosed an improved form of conical anvil provided with a tipprojecting from the apex of the cone and sharp edged ridges extendingfrom this tip and merging with the body of the cone. Anvils of this formare eminently satisfactory for many types of metallic ammunition, butdies for their formation are necessarily somewhat complex and difficultto make. Moreover, the projecting ridges provide a degree ofsensitiveness which for many primers is unnecessary. The presentinvention contemplates an anvil of simpler form which is neverthelessprovided with sharp ridges so positioned as to furnish the abrasionrequired for proper ignition of the priming mixture.

In the drawing:

Fig. 1 is a fragmentary sectional elevation of a cartridge provided withan anvil embodying the present invention.

Fig. 2 is a plan view of the anvil.

Fig. 3 is a side view of the anvil.

Fig. 4 is a sectional elevation of the anvil.

In all of the figures, particularly Figs. 2, 3 and 4, the anvil is shownas greatly enlarged.

The process of manufacturing anvils of this type comprises swaging andcutting them from sheet stock. According to one method, the anvil bodyor point is first swaged to shape and the periphery of the base issubsequently severed from the sheet. The resulting anvil comprises abase I having substantially the thickness of the sheet from which it isswaged and cut. The cutting dies are of such form as to provide flashpassages ll, preferably extending inwardly from opposite sides of thebase Ill. The peripheries of the remaining portions of the base It) maybe cylindrical surfaces, as illustrated in Patent No. 1,900,159, orportions of these cylindrical surfaces may be cut away orflattened, asshown at 12 (Fig. 2), leaving only short cylindrical areas I 3 betweenthe flattened surfaces 12 and the flash passages H.

The anvil is designed to be received in a cylindrical primer cup M(Fig. 1) .and an improved engagement of the anvil with thecup is securedby the provision of the spaced and restricted contacting areas l3.

Extending above the base H1 is the body l5 of the anvil which, accordingto the present invention, has the shape of a truncated pyramid,terminating in a substantially flat top or point Hi. In the drawing, asquare pyramid has been illustrated, but the invention contemplates apyramid of any cross-sectional configuration. The corners 5 I! of thepyramid extend from the point l6 and merge with the upper surface of thebase .10. These corners furnish abrading ridges which facilitate theignition of the priming composition under blow. The configuration of theanvil 10 swaging die is such as to form a conical recess I8 within thebase 50 and a portion of the body IS. The metal bounding thisconical-recess is cut away at the flash passages H, forming thecross-sectional shape illustrated in Fig. 4.

The dies required for the production of anvils of the shape areobviously simple to make and easy to maintain, and the anvils have beenfound to be remarkably effective in the ignition of ammunition primers.

Resort may be had to variations in many of the details without departurefrom the spirit of the invention or the scope of the appended claims.

What is claimed is:

1. An anvil comprising a base of extended area .25 and a body projectingfrom said base, said body being a truncated pyramid terminating in apoint of restricted area.

2. A sheet metal anvil comprising a base hav- I ing side portionsadapted for engagement withthe periphery of a cylindrical cup, flashpassages in said base, and a body extending from said base, said bodybeing a truncated pyramid terminating in a point of restricted area.

3. A sheet metal anvil comprising a hollow interiorly conical basehaving exterior side portions adapted for engagement with the peripheryof a cylindrical cup, and a pyramid shaped body extending from said baseand terminating in a point of restricted area, whereby the corners of 40stricted area, whereby the corners of said pyra- '7 mid form abradingridges extending downwardly 5c and outwardly from said point. g

r 5. An anvil formed of sheet metal and comprising a base ofsubstantially the thickness of the sheet from which it is formed, theperiphery of said base being shaped to furnish a plurality of'55 spacedlimited areas of contact with the periphery of a cylindrcal cup, flashpassages extending through said base,arecess in said base and a pyramidshaped body extending from said base in substantial alignment with saidrecess.

6. An anvil formed of sheet metal and comprising a base of substantiallythe thickness of the sheet from which it is formed, the periphery ofsaid base being shaped to furnish a plurality of spaced limited areas ofcontact with the periphery of a cylindrical cup, flash passagesextending through said base, a recess in said base, and a pyramid shapedbody extending from said base in substantial alignment with said recess,

the corners of said pyramid shaped body intersecting said flashpassages.

7. An anvil formed of sheet metal and comprising a base of substantiallythe thickness of the sheet from which it is made, a recess in said base,a body extending from said base in substantial alignment with saidrecess, flash passages cut in said base and communicating with saidrecess, said body being a truncated pyramid having a point of restrictedarea, the corners of said pyramid forming abrading edges extendingdownwardly and outwardly from said point and intersecting said flashpassages.

h ALLAN CAMPBELL.

